libdisk/md.c

   1 /*
   2  * Copyright (c) 2000-2001 Silicon Graphics, Inc.  All Rights Reserved.
   3  *
   4  * This program is free software; you can redistribute it and/or modify it
   5  * under the terms of version 2 of the GNU General Public License as
   6  * published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it would be useful, but
   9  * WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  11  *
  12  * Further, this software is distributed without any warranty that it is
  13  * free of the rightful claim of any third person regarding infringement
  14  * or the like.  Any license provided herein, whether implied or
  15  * otherwise, applies only to this software file.  Patent licenses, if
  16  * any, provided herein do not apply to combinations of this program with
  17  * other software, or any other product whatsoever.
  18  *
  19  * You should have received a copy of the GNU General Public License along
  20  * with this program; if not, write the Free Software Foundation, Inc., 59
  21  * Temple Place - Suite 330, Boston MA 02111-1307, USA.
  22  *
  23  * Contact information: Silicon Graphics, Inc., 1600 Amphitheatre Pkwy,
  24  * Mountain View, CA  94043, or:
  25  *
  26  * http://www.sgi.com
  27  *
  28  * For further information regarding this notice, see:
  29  *
  30  * http://oss.sgi.com/projects/GenInfo/SGIGPLNoticeExplan/
  31  */
  32
  33 #include <stdio.h>
  34 #include <fcntl.h>
  35 #include <stdlib.h>
  36 #include <volume.h>
  37 #include <sys/stat.h>
  38 #include "md.h"
  39
  40 int
  41 mnt_is_md_subvol(dev_t dev)
  42 {
  43         if (dev >> 8 == MD_MAJOR)
  44                 return 1;
  45         return 0;
  46 }
  47
  48 int
  49 md_get_subvol_stripe(
  50         char            *dfile,
  51         sv_type_t       type,
  52         int             *sunit,
  53         int             *swidth,
  54         struct stat64   *sb)
  55 {
  56         if (mnt_is_md_subvol(sb->st_rdev)) {
  57                 struct md_array_info_s  md;
  58                 int  fd;
  59
  60                 /* Open device */
  61                 fd = open(dfile, O_RDONLY);
  62                 if (fd == -1)
  63                         return 0;
  64
  65                 /* Is this thing on... */
  66                 if (ioctl(fd, GET_ARRAY_INFO, &md)) {
  67                         fprintf(stderr, "Error getting MD array info from %s\n",
  68                                 dfile);
  69                         exit(1);
  70                 }
  71
  72                 /* Check state */
  73                 if (md.state) {
  74                         fprintf(stderr, "MD array %s not in clean state\n",
  75                                 dfile);
  76                         exit(1);
  77                 }
  78
  79                 /* Deduct a disk from stripe width on RAID4/5 */
  80                 if (md.level == 4 || md.level == 5)
  81                         md.nr_disks--;
  82
  83                 /* Update sizes */
  84                 *sunit = md.chunk_size >> 9;
  85                 *swidth = *sunit * md.nr_disks;
  86
  87                 return 1;
  88         }
  89         return 0;
  90 }